Objective: To observe the effects of epoxyauraptene from Aurantii Fructus Immaturus on ulcerative colitis (UC) in BALB/C mice. Method: BALB/C mice were divided into 6 groups:the normal group (normal saline)

the model group (normal saline)

the sulfasalazine group (520 mg · kg-1)

the low-

medium-and high-dose epoxyaurapten groups (80

160

320 μmol · L-1). The UC model was induced in mice by receiving 4% dextran sulphate sodium salt solution for 10 days. All mice received 0.01 mL · g-1 of the corresponding medicines. Disease activity index of BALB/C mice was observed. Colonic mucosa damage repair in mice was evaluated by Colon injury scoring method. The contents of tumor necrosis factor α(TNF-α) and interleukin-10(IL-10) in BALB/C mice colon tissue were determined by using ELISA. Colon smooth muscle myosin light chain kinase expression level was determined by Western blot. Result: Compared with the model group

the disease activity index decreased in the medium-and high-dose epoxyaurapten groups (P<0.05)

colonic injury index decreased

the content of TNF-α in mice tissue decreased in the high-dose epoxyaurapten group (P<0.05)

the level of IL-10 increased

the damaged colon smooth muscle myosin light chain kinase expression decreased in the medium-and high-dose epoxyaurapten groups (P<0.05). Conclusion: Epoxyaurapten has a good effect in treating UC by various kinds of mechanisms in mice.